Device tree aware EMAC driver

Based on BenH's earlier work, this is a new version of the EMAC driver
for the built-in ethernet found on PowerPC 4xx embedded CPUs.  The
same ASIC is also found in the Axon bridge chip.  This new version is
designed to work in the arch/powerpc tree, using the device tree to
probe the device, rather than the old and ugly arch/ppc OCP layer.

This driver is designed to sit alongside the old driver (that lies in
drivers/net/ibm_emac and this one in drivers/net/ibm_newemac).  The
old driver is left in place to support arch/ppc until arch/ppc itself
reaches its final demise (not too long now, with luck).

This driver still has a number of things that could do with cleaning
up, but I think they can be fixed up after merging.  Specifically:
	- Should be adjusted to properly use the dma mapping API.
Axon needs this.
	- Probe logic needs reworking, in conjuction with the general
probing code for of_platform devices.  The dependencies here between
EMAC, MAL, ZMII etc. make this complicated.  At present, it usually
works, because we initialize and register the sub-drivers before the
EMAC driver itself, and (being in driver code) runs after the devices
themselves have been instantiated from the device tree.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/ibm_newemac/tah.h b/drivers/net/ibm_newemac/tah.h
new file mode 100644
index 0000000..bc41853
--- /dev/null
+++ b/drivers/net/ibm_newemac/tah.h
@@ -0,0 +1,90 @@
+/*
+ * drivers/net/ibm_newemac/tah.h
+ *
+ * Driver for PowerPC 4xx on-chip ethernet controller, TAH support.
+ *
+ * Copyright 2004 MontaVista Software, Inc.
+ * Matt Porter <mporter@kernel.crashing.org>
+ *
+ * Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#ifndef __IBM_NEWEMAC_TAH_H
+#define __IBM_NEWEMAC_TAH_H
+
+/* TAH */
+struct tah_regs {
+	u32 revid;
+	u32 pad[3];
+	u32 mr;
+	u32 ssr0;
+	u32 ssr1;
+	u32 ssr2;
+	u32 ssr3;
+	u32 ssr4;
+	u32 ssr5;
+	u32 tsr;
+};
+
+
+/* TAH device */
+struct tah_instance {
+	struct tah_regs __iomem		*base;
+
+	/* Only one EMAC whacks us at a time */
+	struct mutex			lock;
+
+	/* number of EMACs using this TAH */
+	int				users;
+
+	/* OF device instance */
+	struct of_device		*ofdev;
+};
+
+
+/* TAH engine */
+#define TAH_MR_CVR		0x80000000
+#define TAH_MR_SR		0x40000000
+#define TAH_MR_ST_256		0x01000000
+#define TAH_MR_ST_512		0x02000000
+#define TAH_MR_ST_768		0x03000000
+#define TAH_MR_ST_1024		0x04000000
+#define TAH_MR_ST_1280		0x05000000
+#define TAH_MR_ST_1536		0x06000000
+#define TAH_MR_TFS_16KB		0x00000000
+#define TAH_MR_TFS_2KB		0x00200000
+#define TAH_MR_TFS_4KB		0x00400000
+#define TAH_MR_TFS_6KB		0x00600000
+#define TAH_MR_TFS_8KB		0x00800000
+#define TAH_MR_TFS_10KB		0x00a00000
+#define TAH_MR_DTFP		0x00100000
+#define TAH_MR_DIG		0x00080000
+
+#ifdef CONFIG_IBM_NEW_EMAC_TAH
+
+extern int tah_init(void);
+extern void tah_exit(void);
+extern int tah_attach(struct of_device *ofdev, int channel);
+extern void tah_detach(struct of_device *ofdev, int channel);
+extern void tah_reset(struct of_device *ofdev);
+extern int tah_get_regs_len(struct of_device *ofdev);
+extern void *tah_dump_regs(struct of_device *ofdev, void *buf);
+
+#else
+
+# define tah_init()		0
+# define tah_exit()		do { } while(0)
+# define tah_attach(x,y)	(-ENXIO)
+# define tah_detach(x,y)	do { } while(0)
+# define tah_reset(x)		do { } while(0)
+# define tah_get_regs_len(x)	0
+# define tah_dump_regs(x,buf)	(buf)
+
+#endif				/* !CONFIG_IBM_NEW_EMAC_TAH */
+
+#endif /* __IBM_NEWEMAC_TAH_H */